A time-efficient approach for decoupling capacitors placement in a PDN using Sherman–Morrison method for matrix inversion

An incremental-matrix-inversion technique using the Sherman–Morrison formula is used for optimally selecting and positioning decoupling capacitors in a power delivery network (PDN). This technique is incorporated within the particle swarm optimization (PSO) algorithm to minimize the power supply noise by reducing the cumulative self-impedance of the PDN below the target impedance. The performance of the proposed method is compared with the conventional procedure of finding the matrix inverse within the PSO framework. Results show a 37.24% improvement in CPU time to achieve the target impedance as compared to the conventional method.